And this brings us to our second cardinal fact. Lake Michigan, having absorbed or spread over all the vast water-links in the great chain between Superior and Ontario, was the most stupendous body of fresh water on the globe. Its drainage was to the south, through the valleys of the Des Plaines, Kankakee, Illinois, and Mississippi rivers, into the Gulf of Mexico. The evidence of this fact is abundant. The survey of the Illinois Central Railroad shows that the surface of Lake Michigan is three hundred feet above the line of low water in the Ohio River at Cairo, where it joins the Mississippi. It also shows that the low-water line of the Kankakee, where the railroad crosses it, is eleven feet above the surface of the lake. This river, which forms the north-eastern branch of the Illinois, rises in the State of Indiana, near South Bend, two miles from the St. Joseph. From its very commencement at its head-springs it is a shallow channel in the middle of a swamp,--called on the maps the "Kankakee Pond,"--nearly a hundred miles long, and from two to five miles wide. On its north side, in Porter County, is a broad cove, with a small stream in the midst of it, which reaches up due north to within a stone's-throw of the south branch of the East Calumick River, which empties into the south-west corner of Lake Michigan. More than thirty years ago, while traveling by stage from Logansport, Indiana, to Chicago, the writer was told by a fellow-passenger that it was not an unusual thing, on the occurrence of a strong north wind during the spring floods, to cross with boats from this branch of the East Calumick into the Kankakee Pond through this cove. We have not been able to obtain any authentic topographical survey which shows the elevation that must be overcome in order to effect this meeting of the waters.